Item: The Avaluator's Obvious Clues Accident Prevention Values: Are They Replicable?
Title: The Avaluator's Obvious Clues Accident Prevention Values: Are They Replicable?
Proceedings: Proceedings Whistler 2008 International Snow Science Workshop September 21-27, 2008
- Bob Uttl [ Red Deer College, Red Deer, AB, Canada ]
- Meaghen Henry [ Red Deer Colege, Red Deer, AB, Canada ] [ University of Calgary, Calgary, AB, Canada ]
- Jan Uttl [ Avidata.ca, Cochrane, AB, Canada ]
Abstract: The Avaluator Avalanche Accident Prevention Card consists of the Trip Planner and Obvious Clues (Haegeli and McCammon, 2006). For Obvious Clues, the users count the number of obvious clues (e.g., avalanches, loading, terrain trap) and the Avaluator tells them the percentage of historical accidents prevented if historical victims had limited themselves to the same or fewer number of clues (i.e., relative risk reduction). However, the prevention values in the Avaluator differ widely from the values reported by the authors elsewhere as well as from various data sets reported by others. To illustrate, in response to our inquiries into these inconsistencies, Haegeli et al. (2006) recently (on April 16, 2008) revised the published prevention values from 90% to 98% for slopes with 2 or fewer clues and from 47% to 77% for 4 or fewer clues and explained the original values as "typos". In light of these inconsistencies, we attempted to replicate the Avaluator's prevention values using several independent sets of avalanche accident reports. Across all independent data sets, our results reveal much lower prevention values than those reported in the Avaluator. In turn, our results strongly suggests that the prevention values reported in the Avaluator are biased and give users a false sense of security.
Language of Article: English
Presenters: Bob Uttl
Keywords: risk, avalanche prevention, decision making
Subjects: decision making and human factors